Method and apparatus for determining the thermal status of fuel in a line leak detection system

摘要

A method of determining the thermal status of fuel in a fuel distribution system (10) includes pressurizing the distribution line (16) by activating a submersible pump (14) in an underground storage tank (12). Once the distribution line (16) is pressurized, the pump (14) is switched off, and the reverse flow rate out of the distribution line back into the tank (12) is monitored. The test is repeated after a period of time, and the reverse flow rates of the separate tests are compared to determine if the fuel in the distribution line (16) is in thermal stability with the surrounding environment based on flow rate changes between tests.

主权项

1. A method for determining the thermal status of a fuel dispensing system comprising a tank, a pump, a fuel line, a dispensing unit, and forward and reverse flow directions defined by the direction of fuel flow from the tank through the fuel line to the dispensing unit, the method comprising:
activating the pump in order to move fuel forward into the fuel line while the dispensing unit is closed, pressurizing the fuel line; after activating the pump to pressurize the fuel line, deactivating the pump to allow fuel to reverse flow in order to leave the fuel line; after deactivating the pump, measuring the flow of fuel to generate a first set of measurements, the measurements distinguishing between forward and reverse flow; and determining the thermal status of the system based on the first set of measurements.